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    <center>Scilab Function</center>
    <div align="right">Last update : April 1993</div>
    <p>
      <b>logm</b> -  square matrix logarithm</p>
    <h3>
      <font color="blue">Calling Sequence</font>
    </h3>
    <dl>
      <dd>
        <tt>y=logm(x)  </tt>
      </dd>
    </dl>
    <h3>
      <font color="blue">Parameters</font>
    </h3>
    <ul>
      <li>
        <tt>
          <b>x</b>
        </tt>: square matrix</li>
    </ul>
    <h3>
      <font color="blue">Description</font>
    </h3>
    <p>
      <tt>
        <b>logm(x)</b>
      </tt> is the matrix logarithm of <tt>
        <b>x</b>
      </tt>.
    The result is complex if <tt>
        <b>x</b>
      </tt> is not positive or definite positive.
    If <tt>
        <b>x</b>
      </tt> is a  symmetric matrix, then calculation is made by
    schur form. Otherwise, <tt>
        <b>x</b>
      </tt> is assumed diagonalizable. One has
    <tt>
        <b>expm(logm(x))=x</b>
      </tt>
    </p>
    <h3>
      <font color="blue">Examples</font>
    </h3>
    <pre>

A=[1,2;3,4];
logm(A)
expm(logm(A))
A1=A*A';
logm(A1)
expm(logm(A1))
A1(1,1)=%i;
expm(logm(A1))
 
  </pre>
    <h3>
      <font color="blue">See Also</font>
    </h3>
    <p>
      <a href="../linear/expm.htm">
        <tt>
          <b>expm</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="log.htm">
        <tt>
          <b>log</b>
        </tt>
      </a>,&nbsp;&nbsp;</p>
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